Many devices are known for sharpening knives, razors and other sharp instruments and tools. The sharpeners range from whetstones to grinding stones to rubbing straps.
A common problem associated with sharpening knives and the like is the need for properly orienting the sharpener with the blade of the knife. Proper orientation forms a sharp, clean edge with a correctly formed blade angle. However, many people do not possess the skill or experience in holding the sharpener at the correct angle with respect to the blade. This may result in a poorly sharpened blade.